# a = 3
# print(a)
# print(id(a))
# print(type(a))
# b = '我爱你'
# print(b)
# print(id(b))
# print(type(b))
# help
# a = 123
# del a
# print(a)

MAX_AGE = 150
print(MAX_AGE)
MAX_AGE = 200
print(MAX_AGE) 

print("nainxin:",MAX_AGE)